…accomplish this achievement at the same time? Example 2: You have users and groups in your application…. join the same group? Results In both of the above examples you can imagine plenty of concurrent…parent group row so often? INSERT INTO users_groups (user_id, group_id, joined) VALUES (100, 1, NOW…
Post: Avoiding auto-increment holes on InnoDB with INSERT IGNORE
November 29, 2011 By 8 Comments
…concurrency. How can I solve this problem for INSERT IGNORE? As I informed you before, it is not documented that INSERT…INSERT is ignored and no rows are inserted. The same behaviour as INSERT IGNORE: insert into foo(name) select 1 from mutex left outer join… ) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT …
Comment: New Forum Categories: Help Wanted, For Hire
March 5, 2013 By 1 Comment
… query_cache_size = 128M join_buffer_size = 8M long_query_time=300 key_buffer_size = 500M concurrent_insert=2 myisam_sort_buffer_size = 64M…_files_in_group=2 innodb_flush_log_at_trx_commit=1 innodb_flush_method=O_DIRECT innodb_thread_concurrency=16 innodb_buffer… query_cache_size = 128M join_buffer_size = 8M long_query_time=300 key_buffer_size = 500M concurrent_insert=2 myisam_sort_buffer_size = 64M…
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
…inserts (multiple value inserts). Really helps if you have really bulk inserts 100-1000+ values per single insert statement. concurrent_insert – Enables concurrent insert… nice value of 2 which allows concurrent insert to work also if … MyISAM related. join_buffer_size Buffer used for joins without …
Post: INSERT INTO ... SELECT Performance with Innodb tables.
July 12, 2006 By 22 Comments
…similar tables with where clause and joins. It is important for tables … execution, which generally gives better concurrency. However as the name says …tbl2; instead of: INSERT INTO tbl2 SELECT * from tbl1; INSERT … INTO OUTFILE does …no 180 PHYSICAL RECORD: n_fields 2; compact format; info bits 0 0:…
Comment: Why MySQL could be slow with large tables ?
June 20, 2007 By 141 Comments
…. MYISAM table with the following activity: Per day: 1. INSERTS: 1,000 2. UPDATES: 200 3. SELECTS: 1 million Since this is… connect_timeout=5 thread_cache_size=60 key_buffer=750M join_buffer=10M max_heap_table_size=50M tmp_table_size…_slow_queries=/var/log/mysql-slow.log sql-mode=TRADITIONAL concurrent_insert=2 low_priority_updates=1 The problem was that at about…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…query id 188161264 localhost root update insert into child values(2,2) Foreign key constraint fails …Innodb tries to limit thread concurrency allowing only innodb_thread_concurrency threads to run inside… in InnoDB queue” or “sleeping before joining InnoDB queue”. Latest one is quite interesting…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…PAGE_COMPRESS_LIMIT (UNIV_PAGE_SIZE / 2) Q5: When Innodb free…concurrency, srv_thread_concurrency, PLUGIN_VAR_RQCMDARG, “Helps in performance tuning in heavily concurrent…INSERT with multiple values? We build up INSERTS on our clients and insert… ORDER and ORDERLINE tables are joined to form a single …
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…User@Host: msandbox[msandbox] @ localhost [] # Query_time: 2.365434 Lock_time: 0.000000 Rows… QC_Hit: No Full_scan: Yes Full_join: No Tmp_table: No Tmp_table_on… 0.0002 1.00 0.00 INSERT poller_output # MISC 0xMISC 0.8137… Query 4: 0.12 QPS, 0.00x concurrency, ID 0xA766EE8F7AB39063 at byte 4001761 # …
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
…. If we run them concurrently after system reaches steady state we get about 2 req/sec and mysqldump …_mb from innodb_sys_tables as t inner join innodb_sys_indexes as i using(table_id…It is worth to note MySQL actually uses midpoint insertion for its buffer pool replacement policy . Unfortunately by …
